Existing fiber-optic communications networks are typically based on a time-sharing technique whereby time slots in a time frame are assigned to different terminals that generate communications traffic. A great many network protocols for time-sharing within such networks have been disclosed in the prior art, where these protocols are known as time division multiple access ("TDMA") protocols.
One standard implementation of the TDMA approach used in fiber-optic based networks is known as SONET ("Synchronous Optical Network"). SONET uses a simple time multiplexing technique to accommodate increasing numbers of SONET terminals and provides the flexibility needed to transport many digital signals with different capacities.
A major drawback of current systems utilizing SONET transmission facilities is that the user is required to manually enter or specify which time slots are to be used for a requested service. For example, system users may use a GUI ("Graphical User Interface") to specify to an EMS ("Element Management System") which time slots are to be used for the desired service. If, for example, a system user wishes to provision a T1 service between two nodes of a SONET network, the user must enter the time slots (e.g., STS number, VT group, and VT1.5 identifications) into the system so that the system can cross connect the time slots through each node, thus providing the requested path. Additionally, the user must provision T1 ports at each node so that the system may command the network elements to drop the selected time slots at the desired ports. In addition to the disadvantage of manual entry, this approach results in the inefficient utilization and fragmentation of the available bandwidth, as the users are not aware of which time slots are unoccupied in the STS channels and will use whatever time slot they are accustomed to use or is immediately available.
Accordingly, there is a need to provide an automatic system and supporting methods, both being selectively engageable to assign time slots within fiber-optic TDM transmission networks to various services in accordance with a predetermined scheme such that the system provides automatic path selection to the users, avoids bandwidth fragmentation, and optimal bandwidth utilization.